Commonwealth legislation

AD/B747/73 - Stabiliser Limit Switch Assembly

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Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

2/10 complexity

This Airworthiness Directive requires operators of the Boeing 747 models listed in Boeing Service Bulletin 747-27-2228 Rev 1 to carry out the SB’s corrective work before 2 May 1991. It responds to FAA reports of spurious take‑off warning alarms near V1 despite correct stabiliser trim. CASA mandates the SB action, shifting the technical fix from optional to compulsory and placing parts, labour and downtime costs on aircraft operators.

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Current sections

Direct links to the current provisions in AD/B747/73 - Stabiliser Limit Switch Assembly.

AD/B747/73 - Stabiliser Limit Switch Assembly

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

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Boeing 747 Series Aeroplanes

AD/B747/73 Stabiliser Limit Switch Assembly 11/89

Applicability: All model Boeing 747 series aeroplanes as listed in Boeing Service Bulletin 747-27- 2228 Revision 1 dated 26 October 1984.

Requirement: Action in accordance with Boeing SB 747-27-2228 Revision 1 dated 26 October 1984.

Note: FAA AD 89-15-02 refers.

Compliance: Prior to 2 May 1991.

Background: The FAA have advised that reports have been received that even though the stabilizer controls have been set within safe operating limits, air loading on the horizontal stabilizer can cause the take off warning alarm to sound at speeds approaching V1 during take off when trim is set at the end of the “green band”. This condition, if not corrected could result in unnecessary rejected take offs, and the consequent high potential for aircraft incidents and accidents.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/B747/73 - Stabiliser Limit Switch Assembly